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Part of: Grammar points

Capital letters

Last updated: 20 December, 2019

Following this helps people with:

  • time pressures: words in all caps are hard to scan and comprehend

  • stress: if you're anxious you need content that's easy to read

  • multi-tasking: capped words are difficult to read

  • cognitive impairments: easy to read text takes less cognitive load

Guidelines

Capitalised words are not easy to read for many reasons. We're more used to reading words in lowercase letters, so our brains find lowercase words easier to scan and absorb.

1. Do not capitalise whole words or phrases.

2. Use sentence case in headlines and subheads.

3. Use sentence case for buttons.

4. Proper nouns are an exception.

5. Do not capitalise terms, unless they are proper nouns. 

Usability evidence


1. Do not capitalise whole words or phrases.

They are harder to read.

2. Use sentence case in headlines and subheads.

It's easier to scan. 

3. Use sentence case for buttons.

It's easier to scan.

4. Proper nouns are an exception.

It's fine to capitalise the following:

  • names of people, places and things, including buildings and brands

  • specified committee, faculty, department, institute or school: Public Administration Select Committee

  • names of groups, directorates and organisations: Affordable Housing Action Group

  • titles of specific acts or bills: Human Rights Act (but ‘the act’ or ‘the bill’ at second mention)

  • names of specific schemes known to people: Right to Buy

  • names of wars: World War 1 and World War 2

  • job titles following the person's name

  • titles like Mr, Ms, Dr, the Duchess of Cambridge (the duchess at second mention)

  • titles of books: ‘Content Design’

  • header cells in tables: Yearly budget

5. Do not capitalise terms, unless they are proper nouns.

Generally, terms are not proper nouns, so should not be capitalised. Technical terms are not proper nouns. But if a word or term is branded as a distinct thing, treat it as a proper noun. 

Examples:

As a marathon runner, you'll get a medal and a massage.

Not

As a Marathon Runner, you'll get a medal and a massage.

But

I'm running in the Virgin Money London Marathon.

Not

I'm running in the Virgin money London marathon. 

And

We're running a sustainability project.

Not

We're running a Sustainability Project.

But

The Eden Project

Not 

The Eden project


Usability evidence

'The science of word recognition', Mike Jacobs, 2003

A to Z style guide UK government website

'How Capital Letters Became Internet Code for Yelling', Alice Robb, The New Republic, 2014

'100 Things You Should Know About People: #19 — It’s a Myth That All Capital Letters Are Inherently Harder to Read', S. Weinschenk, 2009

'Say hello Writing readable content (and why All Caps is so hard to read)', Marty Friedel, 2015

'The science of word recognition', Mike Jacobs, 2017

‘The Effect of Type Size and Case Alternation on Word Identification’, F. Smith, D. Lott and B. Cronnell, The American Journal of Psychology, 1969. Part-locked: free to access online with MyJSTOR account.

‘Case alternation impairs word identification’ Coltheart, M. and Freeman, R. 2013


Relevant wiki content


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